Hard X-ray emission from the Carina Nebula

Abstract

Hard X-rays above a few keV from the Carina nebula were observed with the Ginga satellite. The hard X-ray emission was found to originate in a region less than 0.15 deg radius from Eta Car. The X-ray spectrum can be described by emission from a thin hot plasma with a temperature of 4.1 keV. The intensity is consistent with the results of previous observations made with large field-of-view instruments, providing allowance is made for emission from the Galactic ridge; however, it is about twice as large as that obtained by the smaller field-of-view SSS on board the Einstein Observatory. At least some of the hard X-ray emission may be extended with a diameter of 0.1-0.3 deg. The X-ray flux from the Eta Car region shows no intensity variations on a time scale between several seconds and 10 yr at a level greater than 30 percent.